Model 3490-3480 -Tapes

A 3480 tape drive is an 18-track cartridge tape device which does not have the data compression feature. A 3490 tape drive is an 18-track cartridge unit which has the data compression feature installed (with a few 36 track exceptions). A 3490E tape drive is a true 36-track cartridge unit. These tape drives actually write in 18-track mode down the entire length of a tape and then reverse to write again on a 2nd set of 18-tracks. This explains why rewind times can be very good for a full 36-track tape -- it`s actually back at the physical load point even though it`s at the logical End-of- Tape (EOT).